The Breakthrough Starshot Project is a US$100 million space research mission unveiled in April 2016 by renowned physicist Stephen Hawking and tech tycoon Yuri Milner that will explore Earth's nearest star system 40 trillion kilometres away. It will see thousands of light-propelled nanocraft launched, traveling at 160 million kilometres per hour, or 20-per cent the speed of light. The unmanned probes are expected to reach Alpha Centauri in just over 20 years - within a lifetime - much sooner than the 30,000 years it would take today's fastest spacecraft.